Lubricating apparatus



E. W. DAVIS LUBRICATING APPARATUS Aug.v 18, 1936.

Filed Jan. 3, 1933 llllll Patented A ug. 18, 1936 Ernt W, Davis,

Oak Park, lll., assignor, by

mesne assignments, to Stewart-Warner Corporation, Chicago, sinia Ill., a. corporation of Vir- Appucauon January a, 193s, serial No. 649,765 11 claims. (ci. zal-47.3)

My invention relatesgenerally to lubricating apparatus and more particularly to improvements in power operated boosters used in high pressure lubricating systems.

In-high pressure lubricating systems in which the parts to be lubricated are equipped with lubricant receiving iittings and lubricant is supplied lby a compressor which has means for making a quick detachable connection with the lubricant receiving fittings, it is frequently extremelyl diicult to uncouple the' compressor from the fitting when the bearing to which the fitting is attached offers a high resistance to the inflow of lubricant. This is especially true of a system employing the so-called pin fittings and a coupler having bayonet slots for engagement with the projecting ends of the pins of the fittings. In the latter system of high pressure lubrication, the lubricant pressure on the coupler .exerts a forcev tending to hold the coupler in tight engagement with the fitting. When the operator attempts to remove the coupling the fitting is often turned loose with the coupler, with consequent loss of time. i'

To overcome this dimculty, it is necessary to provide means in the lubricant compressor for vrelieving the pressure in the discharge conduit. In the past this has been accomplished by providing a valve controlled vent to the atmosphere which could be opened to lpermit the escape o sufficient grease from the discharge conduit to reduce the pressure therein and thus make it possible to disengage the coupler fromthe fitting. This method of relieving the pressure had the disadvantage that a certain quantity of lubricant escaped to the atmosphere each time the vent valve was opened, this grease being wasted and, furthermore, usually adhering to the lubricant compressor, making the latter dirty and difficult to handle.

Another difficulty which has been experienced with high pressure boosters. especially in cold weather, is that the lubricant from the low pressure source failed tol iiow sufficiently rapidly o through the conduit between the source and the booster adequately to prime the high pressure cylinder of the latter. This disadvantage ,is overcome, in my invention, by the' provision of a spring pressed piston operating in a cylinder closely adjacent the inletport of the high pressure cylinder of the booster and operable to force the lubricant into the high pressure' cylinder during the short interval that the inlet port`is open, whenever the flow from the low pressure source is not .vational view of a suiciently rapid fully to prime the high pressure cylinder..

In utilizing compressedair operated boosters in which the discharge stroke of the high pressure plunger is effected by the momentum of an air 5 operated piston, it was found that the reaction of the piston and plunger movement caused high frequency vibration of the booster. This vibration made the operation of this type of booster rapidly tiring to the operator. In the booster of 10v my present invention, this difficulty has been i overcome by providing a handle which is connected to the booster bya pair of links in such manner that the vibrations of the latter are not transmitted to the handle. l5

It is therefore among the objects of my invention to provide an improved high pressure lubricant compressor which is easily operated, which is simple and durable in construction, and which may be economically manufactured.

A further object is to provide an improved booster having a carrying handle connected thereto in such manner as not to have the vibration of the booster transmitted to the handle.

A further object is to provide improved means for insuring positive priming of the high pressure 'cylinder'of a lubricant compressor.

sor upon discontinuance of itsoperation.

Other 'objects will appear from the following description, reference being had to the accompanying drawings, in which- Figure l is a Amore or less diagrammatic elehigh pressure lubricating sysimproved boosterof my intem showing how the vention is utilized; Figure 2 is a central vertical sectional view of the booster.

The booster ofmy'invention is adapted to be used in a high'pressure lubricating'system of one of the types at present in general use, wherein 50 lubricant is forced from a container at relatively low pressure through conduits leading 4tothe booster. The booster is' preferably power operated, usually by compressed air, to discharge the lubricantV supplied from the source through a liliv discharge conduit to a bearing to which the conduit is coupled, under very high pressure. A system of this type is illlstrated in Fig. l. wherein Athe lubricant container comprises a tank I0 in which the lubricant is maintained under relatively low pressure by compressed air supplied thereto through a conduit |2, the supply ofair pressure being controlled by a valve |4. 'I'he tank is usually provided with a safety valve |6 and pressure gauge I6 and has a pipe 20 extending through the top thereof to a point adjacent the bottom. The pipe 20 is connected to a lubricant supply hose 22, while an airsupply hose 24 is connected to the valve |4. 'I'he lubricant supplyhose 22 and air supply hose 24 are preferably bound together byv a suitable wear resisting covering 26.

, f The booster comprises a body 26 having a head 30 secured lthereto by a plurality of screws 32. The head has an air cylinder bore 34 in which thepiston 36 is reclprocable, the piston being guided by its enlarged end portion 36 in the bore 64 and by the reduced diameter portion 40 sliding diameter tip 62 which is arranged to contacty with the face of the check valve 46. 'I'he plunger 60 is guided in a bore 54 formed in the head 36 and is pressed downwardly by a`pin 66, one end of which abuts against the end of the plunger 60 and the other end of whichl contacts with a lug 66 formed on a `trigger 60 which is vpivoted at 62 to a handle 64. Upward swinging movementl of the trigger 66 is limited by engagement of the 'end 66 of the trigger with a lug 66 projecting from the handle 64. The handle is connected to the body 26 ,by a pair of links 10, 1'2, the lower a ends of which are bifurcated and secured to the body by pairs of shouldered studs 14, 16. 'I'he upper end of the link 10 is pivotally connected to` the handle 64 by a bolt 16, while the upper end of link 12 is pivotally connected to the handle by amair of shouldered studs 60. 'I'he studs 14, 16, and bolt 16 form-free pivotal joints, sol that the handie'64 may be freely moved relative to the body 26.

'I'he air supplied upon depression of the trigger- 66 and consequent opening oi' the valve 46 ilows through the passageway 46 into the cylinder34. With the piston 66 in the position shown, the air will flow through ports 62 and bore 64 of the piston 66 into the right hand end of the cylinder l64 and force the piston to the left until lthe ports 6.2 are covered by the shoulder portion of the body at the bore 4 2. The piston` will, however, continue to move to the left, due to its momentum and due to the expansion of the air in the right hand end of the cylinder 34, until the ports 62 pass beyond the edge of the surface of the bore 42 and permit the air from the cylinder 64 toe-escape into a chamber 66 which is in free communication with theatinosphere through a relatively large opening 66. As soon as the air within theright hand end of the cylinder is reduced, approaching atmospheric pressure, the air under pressure in the left hand end oi' the cylinder 64, acting upon the annular surface 60 of the piston 66, will commence forcing the piston 66 to the rightiuntll the ports; 62 again communicate with the supply of rair under pressure, where- .upon the air `will into the right hand end of the cylinder and cushion the return stroke, causing the piston to stop in approximately the position in which it is shown in Fig. 2. This air motor is more fully described and broadly claimed v in my Letters Patent No. 1,630,643, granted November 3,1931. e A

A high pressure lubricant cylinder 62 is secured in a bore 64'formed in the body 26 bya press it, the cylinder havingia bore 66 and being provided with an inlet port 66 and a vent port l |00. A plunger '|02 is reciprocable in the cylinder bore 66, the plunger being sealed by a suit. able leather hat washer |04 4clamped in place by a ring |06 threaded in the end of the cylinder 62 and having its ilangeheld in contact with the l plunger |02 by a spring pressed dished washer- |06. The plunger |02 has a head ||0 formed integrally therewith or formed by a screw threaded therein, the head of the plunger being confined by a sleeve ||2 threaded in the end of the pis- 2 ton 36, the sleeve having a shoulder ||4 of smaller diameter than that of the head ||0. TheY sleeve 4 and head ||0 thus forma lost motion l vdriving connection between the air piston 36 and the plunger |02. 2 IThe grease supply pipe 22 is connected to a. passageway ||6 by a suitable iltting ||6,` thepassageway ||6 terminating in a port |20 which is in registry with the inlet port 66 of the cylinder 62. s 3 A pressure reservoir isprovided in'conjunction with the passageway ||6 to aid in maintaining the pressure therein substantially constant. This pressure reservoir comprises a body |22 threaded in a bore |24 and havingI a cylin- 3 drical bore' |26 formed therein. A cup leather piston |26 is secured to a stem |30 and pressed upwardly by a compression spring' |32. Upward 'movement oi' the piston |26 is limited by the engagement o! the head |34 ofthe stem |36 4 with the end wall |3601' the body |22. Since thereciprocation of the plunger |02 is very rapid, it isnecessary that the high pressure cylinder 66 'be primed veryV rapidly. The spring pressed piston |26 aids in accomplishing this 4 result since it permits the lubricant to il'ow to the booster in a substantially continuous stream, the pressure reservoir serving to store a quantity of lubricant under pressure during the interval that the inlet port 66 of the cylinder 62 is 5 closed by the plunger. l i

The lubricant is forced from the bore 66 of the cylinder 62 by the plunger |02 past a spring pressed check valve |36, which closes the end of the cylinder bore 66. Thence the lubricant ilows through a preferably flexible discharge conduit |40 to a coupler |42, which is provided with a lubricant and spring pressed sealing cup leather |44 adapted to engage the end'of a. pin tltting |46 illustrated as being threaded ina 6( bearing |46 to be lubricated. The coupling connection between the coupler |42 and pin fitting |46 is made by interengagement of bayonet slots |66 in the coupler with the lprojecting ends of a pin |62 in the fitting.

When the fitting is connected to a bearing odering high resistance to the reception of lubricant, the pressure in the discharge conduit |46 and'in the coupler |42 will build up and force .the cup leather |44 rmly vagainst the end of the 7u coil spring |12.

pressure in the discharge conduit and coupler |42, under such circumstances, to permit the coupler |42 readily to be disconnected from a spring pressed check valve |56, and a passageway |58 normally closed during operation of the booster -by a valve |60. The valve |60 is formed at the end of a stem |62 which at vits opposite end carries a cup leather piston |64 reciprocable in 'a cylindrical bore |66. A leather hat washer |68, held in place by a threaded annulus |10, .forms a seal for the stern |62. The piston |64 isnormally pressed to the left by a compression The end of the cylinder *bore |66 is closed by a plug |14 having an inwardly extending portion |16 serving as a stop to limit leftward movement of the lpiston |64. The left hand end of the cylinder bore |66 is connected with the air passageway 44 by a tube |18. From the above, it will beapparent that when the valve 46 is opened'and the booster in operation, the piston |64 will be moved to the right by the air under pressure and the valve |60 held in` a position closing the end of the passageway |58.

To permit escape of air from the plunger cylinder 96, an air bleeding vent valve, comprising a seat part |82 having a needle valve part |84, is threaded in the body 28 and is arranged to permit escape of air through the port |00 in the cylinder 92 'to the atmosphere.` The valve body |82 also serves as a means for aligning the cylinder 92 in the bore 94 of the body 28.

In operation, the tank |0 is lled or partially filled with lubricant, and the hose I2 connected with a source of air under pressure. The valve 'I4 being opened, the lubricant within the tank |0 is placed under pressure and forced to iiow through the pipe 20 to the booster. Opening the valve |4 also permits ow -of air to the hose 24. The coupler |42 is then applied to a fitting' connected to a bearing to be lubricated and the trigger 60 depressed to open the valve 46. The

air flowing into the cylinder bore 34 through the passageway 44 will reciprocate the air piston 36, as previously described, and the latter will' at an intermediate point in its forward stroke strike the head ||0 of the plunger |02 and force the latter forward. The end of theu plunger |02 will not pass the inlet port 98 until after the ports 82 ofthe piston are in communication with the atmosphere through the chamber 66 and port 88. Thus the actual working portion ofy the. stroke of the plunger |02 will be effected solely by the momentum of the piston 36 and the momentum of the plunger itself. This in ertia force is much greater than could be obtained by direct application of air pressure to the piston 36 in the manner customary in fluid operated pumps. As soon as -the valve 46 is opened, air under pressure .will flow from the passageway 44 through the conduit |18 to the left'hand end of the cylinder |66,l andforce the piston |64 to the right to move the valve |60 to closed position. Thus, lubricantejected onl the operating stroke of the plunger |02 will be forced past the check valve |38 through the conduit |40 into the bearing to be lubricated. The grease or other lubricant supplied through the conduit 22 to the passageway ||6 will ow ata substantially continuous rate during the operation of the booster because of the utilization of the pressure reservoir.A

During the time that the plunger |02 covers the port 98, the lubricant will ow into the 'bore |26 of the pressure reservoir body |22. comprising the spring |32. Then upon the retractile stroke of the plunger after it has uncovered the port 98, the spring |32 will expand and aid ink forcing a priming charge of lubricant into the cylinderbore 96.v

After suicient lubricant has been supplied to the bearing, the trigger 60 is released, the check valve 46 will be closedby its associated spring, supplemented by the pressure oi the am, and force the valve .operating plunger 50 and the operating rod 56 upwardly to move the trigger to the position shownfin Fig. 2. Upon the closure of the valve 46, the air pressure within the passageway 44 will be rapidly dissipated through operation of the piston 36 and slight leakage from the cylinder f bore 3.4, whereupon the spring |1'2'Will force the piston |64 vto the left, removing the valve |60 from its seat. If the' bearing to which the coupler -is` connected is of low resistance, the pressurein the discharge-conduit Will drop rapidly,.so that no diiculty will be experienced inremoving the coupler from the fitting. If,'h`owevcr, the bear-l ing offers high resistance to the admission of" lubricant, the pressure within the discharge conduit |40 would'be maintained and make it diicult to disconnect the coupler from the fitting, were it not for the opening of the valve 60, which permits lubricant to ow past the vcheck valve |56 through the duct |58 into the passageway ||6,

in which the lubricant is, of course, at relativelyk low pressure. vWith the provision of the pressure release valve |60, the pressure witliin the discharge conduit |40 will drop almost immediately, upon cessation of the booster, approximately to that of the lubricant within the passageway ||6. At this low pressure the coupler may be disconnected easily from the fitting."

' Since the booster pump operates upon an inertia principle, utilizing the momentum of the moving parts to eiect the discharge stroke of the plunger, the booster as a Whole is subject to relatively high reactive forces. The reciprocation of the plunger and airpiston is extremely rapid,

and it would thus be very tiring ifit were endeavored to hold'the plunger body tightly in the hand while using the apparatus. However, with the provision f the handle 64, which is freely movable relative to the body of the booster, the vibration and shock are not transmitted to the operators hand to any noticeable extent, and the booster may therefore be used for extended periods without tiring the operator. It will be noted, in this connection, that the trigger for controlling the valve |46 moves with the handle, and that there is an articulated operating connection between the trigger and the valve operating plunger.

While I have shown and described a particular embodiment of my invention, it Will be'apparent to those skilled in the art that various modifications in design and construction may be'made without departing from the spirit of my invention. What I claim as new and desire to secure by LettersPatent of the United States is:

1. In a high pressure lubricating system, the combination of a source of lubricant under pressure, a pumping mechanism connected to receive lubricant from said source and to discharge it .under high pressure, a discharge conduit for connecting said pumping mechanism with a part to be lubricated, power means for operating said pumping mechanism, a valve-controlled by-pass from said discharge conduit to said source. and

rsl

means controlled by said power means for holding thesvalve in said by-pass closed while said power means 4is in operation and opening said valve upon cessation of operationot said power means.

i 2. A pneumatically operated booster for high pressure lubricating apparatus comprising an air motor, a lubricant ejecting pump operated by said l-said manually operable valve for actuating said' by-pass valve. a

3. In a fluidpressure operated lubricant compressor, lthe combination of lubricant pumping i mechanism, a fluid operated motor to actuate said mechanism, a source of lubricant under low pressure connected to said pumping mechanism, a lubricant discharge conduit having means at its end to make a detachable connection with a lubricant receiving tting, al duct leading from said discharge conduit to a part 0L said mechanism receiving lubricant under low pressure from said source, a iluid `pressure operated valve in said duct, and a manuallyv operated valve to admit iluid under pressure to said motor and to said fluid pressure 4operated valve.

4. In a high pressure lubricating system, the

lcombination of a source of lubricant under pres` sure, a pumping mechanism connected to receive lubricant from said source and to discharge it under pressure, a discharge conduit for connecting said pump with a part to be lubricated, fluid pressure operated means for actuating said pump, a valve-controlled by-pass from said discharge conduit to said source, and iluid pressure operated means for holding -the valve in said by-pass closed while said .power means is in operation.

5. A pneumatically operated booster for high i pressure lubricating apparatus comprising an air motor, a. high pressure lubricant electing pump operated by said air motor, a manually operable valve controlling the admission of air under pressure to said air motor, adischarge conduit connccted to saidv pump for feeding lubricant to parts to be lubricated, a by-pass co'nduit for permitting escape o1' lubricant from said discharge conduit, a valve in said conduit, and air pressure operated means for controlling said last named valve, said means being connected to be Asupplied with air under pressure upon the opening oi' said manually operable valve.

6. In lubricating apparatus, the combination of va source of lubricant under relatively lowpres'- sure, a high pressure booster operable independently of the pressure of the lubricant from said source and having a cylinder with an inlet port, a lubricant conduit between said source. and said booster, and a pressure reservoir associated with said booster and arranged to` store lubricant under pressure during the time that the inlet port 'of the latter is closed and to discharge the lubricant to said cylinder upon opening ot said inlet port, said reservoir being of variable eiIective size and having resilient means opposing the lubricant pressure therein to decrease its size.

7. In high pressure lubricating apparatus, the

combination of a source oi lubricant under low pressure, a booster operable independently of the pressure of the lubricant from said source and having a high pressure cylinder with an inletport booster.

8. A portable power operated lubricant compressor, a handle therefor; links pivotally connected to said handle and to` said compressor, an element for controlling the operation of said compressor, said element beingmounted on said handle, and anarticulated connection between said control element and. said power means to control the operation of the latter. I

9. A portable power operatedbooster for high pressure lubricating apparatus comprising a body, a pairoi links pivotally connected to said body, and ahandle for supporting said booster and having its ends pivotally :connected to the ends o'f said links respectively.

10. A manually portable power operated lubricant pumping mechanism, a handle for supporting said mechanism, and means for connecting said mechanism, said-'handle and means being constructed and arrangedto permit substantially free relative movement of said mechanism and saidv handle.

l1. A portable power operated lubricant compressor having rapidly moving parts which tend to vibrate the compressor in opposite directions, a handle for supporting said compressor, 'and a yielding conncctionbetween said compressor and said handle, said connection being arranged to permit substantially free movement of said compressor relative to said .handle directions. A 

